Transcript for Prosecution Delivers Closing Argument in George Zimmerman Trial

As we begin tonight it was a day of high drama in the george zimmerman trial, closing arguments and prosecutors gave it all they had, trying to convince a jury of six people that zimmerman is guilty of murder or manslaughter in the death of trayvon martin. Zimmerman normally stoic finally showed a silent reaction. Abc's matt gutman was there. Reporter: It was a closing argument laden with emotion. A teenager is dead. He is dead through no fault of his own. He is dead because another man made assumptions. Reporter: And theatrics. Oh, he's skipping away. La, la, la. That's what he's claiming. Reporter: Prosecutor bernie de la rionda had george zimmerman cred ability in the cross hairs, suggesting he lied that night. He claims the victim was -- how is he going to talk? Or is he lying about that? Reporter: De la rionda using power points. This foam man win and zimmerman's own words to try to convince the jury that zimmerman murdered trayvon martin for the way he looked. He automatically assumed that trayvon martin was a criminal. Reporter: And again today jurors shown pictures of martin's body. This is one of the last photos that will ever be taken of trayvon martin. And that is true because of the actions of one individual, the man before you, the defendant, george zimmerman. Reporter: One juror turned away. Another seemed to nod in agreement as de la rionda ripped into zimmerman's cred ability. Do you believe that there is an innocent man sitting over there right now? Throughout zimmerman stared blankly t his chair pointed straight ahead. Barely moving until this moment. The man before you, george zimmerman, the man who was guilty of second degree murder. Reporter: Diane, saw zimmerman looking almost detached. His attorney tells me that he is under immense pressure. He knows his life is permanently changed. If he's convicted he could spend the rest of his life behind bars. If he's acquitted he could spend the rest of his life heigiding. I want to bring in dan abrams who followed this case from the start. Should george zimmerman be worried tonight? How worried? We should absolutely be worried. It's still an uphill battle for prosecutors. But this was a very effective closing argument, focusing on an issue we discussed last night which is the human aspect of this, the emotional aspect of this. The notion that this is a 17-year-old kid who didn't need to die. It is possible that jurors will simply look at that issue alone and say the letter of the law is one thing but the practical reality is another and this is a kid who shouldn't be dead. Something wrong happened. That's right. So manslaughter is a possible charge now. This is new today, right? That's right. That is a big win for the prosecution. Allows jurors to compromise the difference being that in one case, murder, you have to show the intent to kill. In another case it could be a reckless, extremely negligent killing. Again for the juror we're talking about six people. They are all female and tomorrow what will happen? The defense is going to get an opportunity to give its closing argument. They're both going to have to respond to what they already heard and move forward with their own argument, knowing that the prosecution will have the final word. Each side gets three hours but the prosecution gets to break it up, getting the first word and the last word because they have the burden of proof. Thank you once again tonight.

This transcript has been automatically generated and may not be 100% accurate.